ESPN is currently running a contest where site users choose their favorite ballparks. It is a head to head bracket style voting. Target Field is currently winning by the largest margin (at least when I voted). It is up against Oakland co. Coliseum. When I voted it was 92% TF to 8% O.co.
Here is a link to vote:
http://espn.go.com/mlb/story/_/id/80...-vote-mlb-best
Edit: Camden Yards was also beating Rogers Center 92% to 8%.

